<File Color="Color.Primary" OnChange="upload"></File><br>
<File Color="Color.Info" OnChange="upload"></File><br>
<File Color="Color.Warning" IsBoxed OnChange="upload"></File><br>
<File Color="Color.Danger" IsBoxed HasName OnChange="upload"></File><br>

@code{

    void upload(InputFileChangeEventArgs e)
    {
    //上传逻辑
    //https://docs.microsoft.com/zh-cn/aspnet/core/blazor/file-uploads?view=aspnetcore-5.0
    }

}